ORA-00230: operation disallowed: snapshot control file enqueue unavailable

User might encounter below error, in case if RMAN backup is already running and user might have triggered another backup. The second backup must wait control file enqueuer to create a snapshot of the controlfile.

RMAN-03002: failure of backup command at 04/10/2020 16:40:33
ORA-00230: operation disallowed: snapshot control file enqueue unavailable
You can run below command to find out the backup that is running and causing the wait

SELECT S.SID, USERNAME , PROGRAM, MODULE,
ACTION, LOGON_TIME FROM V$SESSION s, V$ENQUEUE_LOCK l
WHERE l.SID = s.SID AND l.TYPE = 'CF' AND l.ID1 = 0 AND l.ID2 = 2;

To avoid this error make sure that backups are not overlapping each other.

Regards,
Satishbabu Gunukula, Oracle ACE
http://oracleracexpert.com